The intention here is to encourage students to test various materials and through investigation recognise that only a few metals have magnetic properties. An important point to be made is that in our everyday experience most metals appear to be magnetic because the most widely used metal is steel containing iron. This is made more difficult for students to explore because they must have at least two magnets of comparable strength and many of the familiar advertising fridge magnets used for simple investigations are weak and constructed in a way that they have no identifiable magnetic poles.
The surfaces of these magnets are well protected and will reduce the risk of students accidentally pinching fingers or the magnets shedding fragments if handled roughly. Ask the students to investigate what they need to do to make the magnets attract and repel each other.
Have them identify different ends of each magnet with identifying stickers. How well can the students predict what will happen when the magnets are brought near to each other? Now encourage students to use masking tape to fix one magnet onto the roof of a toy car. Use the hand held magnet to push the car along without touching it or to attract the car towards it by changing its orientation. Can students predict if the magnet on the car will be attracted or repelled by the approach of a new magnet?
The intention here is for students to recognise that magnets can repel as well as attract each other. At this level it is not considered important for students to be able to recall that like poles repel and unlike poles attract, but to recognise that magnets can repel and attract without making physical contact and that their orientation is important. Students can be encouraged to investigate if magnetic forces pass through other non magnetic materials.
To capture student interest, place a magnet such as a fish tank glass cleaning magnet on a classroom table. Introduce another magnet the other glass cleaning magnet under the table so the two are strongly attracted. Position the magnet so you can move the magnet under the table with your knee or other hand. The magnet on the table top will follow the movement of the magnet below. Next have them fix a paper clip to a length of cotton with sufficient length to reach from the table top to the magnet.
Encourage students to investigate if various materials will stop the magnetic force of attraction when they are introduced between the magnet and the paper clip.
Try sheets of paper, glass, tile, aluminium foil, copper and zinc sheet. Do any of these materials have an effect on reducing the magnetic force? The intention here is for students to observe that magnetic forces will remain unhindered and can travel through most materials without any effect.
Collect a number of uncoated wire coat hangers and cut and straighten them into short lengths which range from 10cm to 20cm long. Distribute a couple of these around to students working in pairs or triplets, making sure they are given different sized lengths. Also pass around a number 5 to 8 of small paperclips to each group. Deliberately do not pass out any magnets just yet to avoid students bringing them into contact with the wire lengths.
Encourage the students to investigate if any of the lengths of wire are successful in attracting any of the paperclips. It has become magnetized. Other metals, like copper or gold, are not attracted to magnets. Magnets can also attract each other, but only if they face in opposite directions. A magnet has two ends called poles; one end is the north pole and the other is the south pole. A north pole will attract a south pole; the magnets pull on each other.
But the two north poles will push each other away. We say the magnets repel each other. Magnets seem to act something like positive and negative electric charges. Electricity and magnetism are very closely related. If the words north and south remind you of anything, the earth is in fact a giant magnet. For information on user permissions, please read our Terms of Service.
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Students learn how the sun's activity and magnetism drive space weather and impact Earth's living and technological systems. Join our community of educators and receive the latest information on National Geographic's resources for you and your students.
Skip to content. Twitter Facebook Pinterest Google Classroom. Encyclopedic Entry Vocabulary. Geomagnetic Poles The Earth is a magnet. The iron in the sand is magnetic, strongly attracted to the magnet on an atomic level. Media Credits The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
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